The present invention relates to a method for operating an electromechanically operable and/or electromechanically lockable parking brake for motor vehicles substantially comprising an operating element, an electronic control unit, to which are sent wheel speed values from wheel speed sensors, at least one unit for generating a brake application force, and electromechanically lockable brake devices on at least one axle, with said brake devices being adapted to be applied by the unit. The invention further relates to a parking brake for motor vehicles for implementing the method.
DE 198 34 129 C1 discloses a parking brake for motor vehicles which provides each one actuator on at least two wheel brakes applying its associated wheel brake by means of a cable pull. Further, the mentioned publication discloses a method for actuating a parking brake, according to which the application force of the actuator depends on the speed of the motor vehicle and, in addition, prevents locking of the wheels being braked by the actuator. The prior art method suffers from the disadvantage that the method cannot be implemented without wheel speed values which represent the speed of the motor vehicle and also exhibit a possible locking of the wheels being braked by the actuator.
German published patent application DE 198 36 687 A1 discloses an electronic parking brake system and a method of operation therefor. In this publication, the vehicle speed is sent as an input signal to the electronic parking brake system in order to determine the driving situation of the motor vehicle. However, when the wheel speed values of the motor vehicle wheels are not available, it is impossible to implement the method disclosed.